"深入解析MTK LCD驱动代码及初始化流程"

/*给定的mdpath 表示目的文件的绝对路径名,如果没有指定合适的目的路径或者mdpath所指的文件不存在,则写入错误信息并返回-1*/ int write_to_and_from_qvfb_mutex(const char *mdpath, const void *toput, PIC_LENGTH_T putlen, void *toget, PIC_LENGTH_T *getlen) { int writekey; int readkey; void *shmp; int ret; if (mdpath == NULL || toput == NULL || putlen <= 0 || toget == NULL || getlen == NULL) { fprintf(stderr, "[%s] mdpath is NULL\n", __FUNCTION__); return -1; } do { if ((writekey = open_shmem(mdpath, &shmp, O_WRONLY | O_CREAT, QVFB_SHM_PERM)) < 0) { fprintf(stderr, "[%s] open_shmem failed to get write key\n", __FUNCTION__); ret = -1; break; } if ((readkey = open_shmem(mdpath, &shmp, O_RDONLY, QVFB_SHM_PERM)) < 0) { fprintf(stderr, "[%s] open_shmem failed to get read key\n", __FUNCTION__); ret = -1; break; } if ((ret = lm_flush_md($mdpath, shmp, toput, putlen)) < 0) { ret = -1; break; } if ((ret = lm_image_get($mdpath, shmp, toget, getlen)) < 0) { ret = -1; } close_shmem(mdpath, shmp, writekey, writekey); close_shmem(mdpath, shmp, readkey, readkey); } while (0); return ret; } #endif // #ifdef HAVE_LIBJPEG